Automotive alternators that use Lundell rotors have been used in automobiles for decades. Loads from electrical equipment that is mounted due to environmental issues have been increasing rapidly in recent years, and further increases in generated power are being sought from Lundell rotors.
Conventionally, in order to solve such problems, electric machine rotors have been proposed in which resin fans that rotate together with pole pieces have pockets, and permanent magnets are insert-molded into the pockets so as to be held by the fans (see Patent Literature 1, for example).
Patent Literature 1: Patent Publication No. 2002-527015 (Gazette)